Twelve (12) healthy elderly subjects were divided into two groups: (a) those given an antioxidant/NO-modulating fermented papaya preparation (FPP) 9 g/day for 4 weeks, and (b) a placebo group. No protein/lipid distribution in erythrocytes (RBC) membranes was noted among different ages and treatments. Higher RBC concentration of malondialdehyde and nitric oxide synthase were found in the elderly (p < 0.05 versus "young" controls), whereas superoxide dismutase was unaltered. Such abnormalities were prevented by FPP supplementation (p < 0.01). RBC and RBC ghosts showed an enhanced susceptibility to lipid peroxidation by using cumene hydroperoxide (p < 0.01 versus young) but FPP supplementation significantly protected intact RBC (p < 0.05). These preliminary data suggest that nutraceuticals with antioxidant/NO-regulating properties significantly protect from RBC oxidative damage, and are potential weapons for the aging process and chronic and degenerative diseases.